The best way to set off a fire alarm
What does not often happen is the crucible exploding.
It was not a large amount of magnesium, so it was pretty much contained. Just a very loud pop. (I did not get hurt, and luckily everyone was safe.)
However, it was enough of an surprise to set off the fire alarm and quite possibly release of all of the adrenaline that I had stored up in my glands.
And so in one of my first chemistry courses ever, I evacuated my entire high school. And made them all stand outside for the entire period as it was not a scheduled fire alarm, nor was it a simple prank pull. And I did not go to a small high school. It was over 2000 students.
Many of my friends were taking an exam in American History. It was postponed to the next week as a result of my experiment. They very much appreciated my work.
The accumulation of the excitement, investigating a unique occurrence (there was a crack in the crucible), and the acceptance of my peers all in one small event is what hooked me. I somehow must have known that one has the opportunity to study conservation of energy in a controlled manner though bomb calorimeters.
* I know that HS experiments can go very wrong and am thankful now for the insight and attention to safety my teacher had. It is very tragic when a teacher is not so careful as evidenced here and here